Rheostat



Jul 15', 1924. 1,501,638

R. E. WEiMER ET AL RHEOSTAT Filed May 6. 1921 WITNESS INVENTORS F/F}i/yvor7 %MM/Q'% Patented July 15, 1924.

UNITED STATES ROBERT E. WEIMER AND MATZ A. SPEIGHER, OF COLLIERS, SIGNO'RS TO WEIMER-WARREN COMPANY, OF COLLIERS,

PORATION OF WEST VIRGINIA.

PATENT OFFICE.

WEST VIRGINIA, AS- WEST VIRGINIA, A con- RHEOSTAT.

Application filed May 6,

T all whom it may concern;

' Be it known that we, ROBERT E. WEIMER and MATZ A. SPEIoIIER, citizens of the United States, both residing at Colliers, in the county of Broo re and State of est Virginia, have invented a certain new and useful Improvement in Rheostats, of which the following is a specification.

This invention pertains to the electrical art known as rheostats or resistance mechanisms and is designed primarily as an improvement over that special branch of rheostats employing grids in parallel series and held in contact by a securing bolt feature. Our invention resides particularly in the means employed for providing a positive and non-separable contact union between the plurality of current conducting resistance bars, wholly independent of the securing bolt, together with certain other advantageous features that will be readily apparent when further described in detail. The apparatus will be of special value and utility when used in conjuction with high duty motors that must be constantly stopped and started, its exact size and construction being determined by the particular use to which it is to be applied.

In the accompanying drawing, we have il lustrated one practical embodiment of our invention, the same being merely illustrative and hence subject to more or less n1odification in its detail form of construction and arrangement of coordinate elements that will confine invention within the scope of the appended claims.

Referring then to said drawing, Figure 1, is an elevation of one unit or series of contiguously associated resistance bar elements, the cut-out or switch connections thereto being shown by dotted lines; Figure 2 is a view in perspective of a segment of said re sistance unit and Figure 3 shows an apertured housing or securing plate member. The essential constructive features of our improved rheostat embodies a suitable supporting housing or frame work, consisting of apertured end plate members 1 provided with flanged portions 2 for securing the plates, by adequate bolt means, to a slate or other base 3, all of which is of ordinary usage and no invention is claimed for this particular feature, per se.

The resistance bars 42., which we employ, are preferably made from sheet steel, or

1921. Serial No. 467,353.

othersuitable substantially flat metal of a highly resisting nature, and of a pro-determined gauge and area, the same being provided with suitable sized apertures 5 at both ends for the reception of an insulating tube 6, through which tube is inserted a securing bolt 7 and the entire plurality of bars comprising each series held thus in aligning, immovable position by means of ordinary nuts 8. Each bar throu hout the entire series is rigidly and positiveIy joined or connected by a rivet or other adequate fastening means 9, at both end sections thereof, this said securing feature being carried out whereby one end of each bar will be joined to the adjacent bar at one side thereof, while the opposite end is likewise joined to the adjacent bar at the other side. This oppositely disposed connecting feature between the entire plurality of bars constituting the series, provides a zigzagging course orv path forward and back for the electric current.

The normal intended inclination of the associated connected bars will be slightly angular in their corelated positions, that is to say, not in exact parallel alignment, a predetermined separation or air cooling space being thus provided for a well known purpose between all the bars, insulating washers 10 being provided in these spaces, the same being seated around and contacting with the aforesaid insulating tube 6.

The said resistance bars are also adequately insulated from the supporting end frame sections 1, thereby wholly confining the path of the electric current within the said series of bars.

At stated intervals throughout the length of each series a certain bar is extended out beyond the remaining bars, thus providing a plurality of terminals 11 for con nection with the cut-out switch 12. These said terminals preferably involve a wire clamping member 13 controlled by a small bolt 14. As shown, all of thesesaid exten sion bars are made from a somewhat heavier gauge metal than the remaining bars.

In the event of there being more than one series of bars constituting the resistance rheostat, the usual procedure of positioning any plurality of units in either stack formation or else, as a substitute arrangement, in horizontal alignment, will be carried out, a suitable apertured connecting bar or conduct-or 15 being utilized between the first or bottom -unit, at any convenient location, and so on throughout all the units comprising the rheostat.

Current is furnished to the rheostat through the positive wire ltifrom the generator, not shown, connection being made with one extreme end terminal 11 by means of the clamping device 13, or other adequate means, still another positive line wire connection 17 being made from the controller lever 12 with the rnotor, not shown, the return, or negative line from the motor to the generator, being ind cated by 18. The path of the current through the plurality or series of rigidly connected resistance bars comprising the rheostat, will be lengthened or shortened according as the said controller lever is moved into engagement with the various radially positioned contacts, or the resistance can be i; cut-out entirely by simply moving'the said lever to a neutral position, or out of engage nient with the series of contact points. Vhat we claim as our invention is:

1, Ina rheostat, a series of separate metal bars, each except one at each end of the rheostat having each end electrically connected to one bar at each side thereof so as tofform a continuous zigzag path for electric current, the angles of the zigzag path 3Q being made by-the union of the ends of two ars- 2. In a rheostat, a series of metal bars arranged in a zigzag manner to form a continuous path for electric current, some of the bars being prolonged beyond the zigzag structure to provide electric terminals.

3. In a rheostat, a series of separate metal bars, each except one at each end of the rheostat having each end electrically connected to one bar at each side thereof so as to form a continuous zigzag path for electric current, the angles of the zigzag path being made by the union of the ends of two bars in combination with a frame, and an inl sulating support carried by the frame and threaded through openings in the said bars.

A rheostat, a series of separate metal bars, each except one at each end of the rheostat having each end electrically connected to one bar at each sidethereof so as to form a continuous zigzag path for electric current, the angles of the zigzag path being made by the union of the ends of two bars in combination with a frame, an insulating support carried by the frame and threaded through openings in the said bars, and means for mechanically uniting the said electrically connected ends of the bars.

Signed at Colliers, West Virginia, this 18 day of April, 1921. p

7 ROBERT E. lVEIMER. MATZ A. SPEICHER 

